DR ROY SPENCER, PHD Principal Research Scientist at the University of Alabama in Huntsville and US Science Team leader for the Advanced Microwave Scanning Radiometer on NASA’s Aqua satellite. Recipient (with John Christy) of the Exceptional Scientific Achievement Award from NASA and the American Meteorological Society’s Special Award for his work in satellite-based temperature monitoring. Formerly Senior Scientist for Climate Studies at NASA’s Marshall Space Flight Center.
So, if “we have no way of knowing how cold (or warm) the globe actually got”, how did the IPCC know it’s hotter than it’s been for a thousand years?
On January 27th 2005 Dr Spencer wrote
126 : As you might imagine, it’s a little difficult to construct a temperature history for a period of record that, for the most part, had no reliable thermometer measurements. Since good thermometer measurements extend back to only around the mid-1800s, “proxy” measurements, primarily tree ring data, have been used to extend the temperature record back additional centuries… The claim of unprecedented warmth and the hockey stick shape appear to hinge on the treatment of one species of tree, the bristlecone pine, from North America in the 1400s. Further statistical tests showed that this critical signal in the early 15th century lacked statistical significance. This suggests that the results of Mann et al were simply which greatly exaggerated a characteristic of the bristlecone pines, which may or may not be related to global temperatures.
The original Mann et al article has had huge repercussions. The hockey stick, along with the “warmest in 1,000 years” argument, has become a central theme of debates over the Kyoto Protocol, a treaty to limit emissions of greenhouse gases, in governments around the world. The question begging to be answered is: Why did the IPCC so quickly and uncritically accept the Mann et al hockey stick analysis when it first appeared? I cannot help but conclude that it’s because they wanted to believe it.
Dr Spencer pointed out what should have been obvious that the hockey stick had never been subjected to one of the most basic tests of science: Unusual claims in science should be met with unusual skepticism, and this did not happen with the Mann et al study.
An increasing number of researchers have anecdotal evidence that the science tabloids, Nature and Science , select reviewers of some manuscripts based upon whether they want those papers to be accepted or rejected. In other words, it seems like the conclusions of a paper are sometimes more important that the scientific basis for those conclusions. Since those periodicals have profit and popularity motives that normal scientific journals do not, maybe the time has come to downgrade the scientific weight of publications in those journals, at least for some purposes… It will be interesting to see if the IPCC, and its member countries, continue to rally around the hockey stick, or discard it.
